Dymarskii, Y.M. (2002) “Manifolds of Eigenfunctions and Potentials of a Family of Periodic Sturm–Liouville Problems”, Ukrains’kyi Matematychnyi Zhurnal, 54(8), pp. 1042–1052. Available at: https://umj.imath.kiev.ua/index.php/umj/article/view/4145 (Accessed: 10 April 2025).